TABLE 1.

Stringent response components that contribute to virulence

PathogenStringent response machineryPathogenesis-related phenotype(s) associated with ppGppReference(s)
Gammaproteobacteria
    EHECRelA, SpoT,a DksAAdherence 143
    UPECRelA, SpoT,a DksAAdherence 1-3
    P. aeruginosaRelA, SpoT,a DksAQuorum sensing, biofilms, antibiotic tolerance 18, 24, 27, 63, 202, 205
    Y. pestisRelA, SpoT,a DksAdBubonic infection, lung dissemination 190
    V. choleraeRelA, SpoT,a RelV, DksAdMouse colonization 56, 57, 74, 84, 179
    E. carotovora subsp. atrosepticabRelA, SpoT,a,d DksAdRot in potato tubers 207
    S. flexneriRelA,d SpoT,d DksAIntercellular spread 133, 175
    S. enterica serovar TyphimuriumRelA, SpoT,a DksAInvasion (SPI1 dependent), intracellular replication (SPI2 dependent) 159, 182, 197, 200, 210, 223
    S. enterica serovar GallinarumRelA, SpoT,a DksAdInvasion (SPI1 independent), intracellular replication (SPI2 dependent) 97
    L. pneumophilaRelA, SpoT,a DksAMacrophage transmission 53, 81
    F. tularensisRelA, SpoT,a DksAdPhagosome escape in macrophages 43
Actinobacteria
    M. tuberculosisRelMtb,a CarDPersistence in mice 52, 185
Firmicutes
    L. monocytogenesRelA,a RelQ,d RelPdAdherence, intracellular survival 19, 118, 149, 196
    S. aureusRelA,a RelQ,d RelPdEssential for viability in vitro 44, 71, 114
    B. anthracisRelA,a RelQ,d RelPdSporulation 114, 204
    C. difficileRelAaAntibiotic tolerance 62
    E. faecalisRelA,a RelQAntibiotic tolerance, virulence in C. elegans 4, 218
    S. pyogenesRelA,a RelQ,d RelPd 186, 187
    S. pneumoniaeRelSpn,a RelQPulmonary infection of mice 17
    S. mutansRelA,a RelQ, RelPBiofilms 114-116, 145
Alphaproteobacteria
    Brucella sp.Rsh, DksAdMacrophage survival, persistence in mice 59, 104
    R. etlicRelA,a DksAdNodule formation and nitrogen fixation 25, 39, 137
    S. meliloticRelA,a DksAdNodule formation 211, 213, 214
    A. tumefaciensbRelA,a DksAdTi plasmid transfer 206, 221
Epsilonproteobacteria
    C. jejuniSpoT,a DksAAdherence, invasion, intracellular survival 70, 188, 220
    H. pyloriSpoTaMacrophage survival 138, 212, 224
Spirochetes
    B. burgdorferiSpoT or RelBbuaVirulence in mice 34-36
  • a Bifunctional synthetase/hydrolase.

  • b Plant pathogen.

  • c Plant symbiont.

  • d Protein encoded by the species but yet to be studied.